A comprehensive exploration of Na ion transport in NaSICONs using molecular dynamics simulations.

Scandium-substituted Na Sc Zr Si P O NaSICONs have emerged as promising electrolyte materials for all-solid-state sodium batteries. However, the comprehensive investigation of these multi-element structures is challenging due to their vast compositional space, leading to a limited number of compositions explored thus far. In this study, we address this issue by employing low-cost, yet high-precision force field molecular dynamics simulations based on density functional theory to investigate the Na mobility and resulting conductivity in Na Sc Zr Si P O (0 ≤ ≤ 3; 0 ≤ ≤ 2). Our findings show that the incorporation of Sc- and Si-substituents enhances the conductivity, achieving values of 10 S cm at room temperature for moderate to high substitution degrees. Moreover, our study demonstrates the efficacy of the applied methodology for large-scale screening, enabling the exploration of extensive configurational spaces of NaSICONs and other materials for potential use as solid-state electrolytes.